Field
The present invention relates to a rubber composition based on one or more functionalized diene elastomers and on one or more carbon blacks with a particular CTAB specific surface, and to a semi-finished article comprising it, and to a tire incorporating such a semi-finished article.
Description of Related Art
Now that savings in fuel and the need to protect the environment have become a priority, it is desirable to produce mixtures having good wear resistance properties while having a hysteresis which is as low as possible in order to be able to process them in the form of rubber compositions which can be used in the manufacture of various semi-finished products participating in the composition of tire casings, such as, for example, underlayers, sidewalls or treads, in order to obtain tires having an improved wear resistance without damaging the rolling resistance. Safety during braking on a wet surface is also a result which has to be maintained. Finally, productivity constraints are also resulting in the need not to be disadvantageous to, indeed even to improve, the processing of the mixtures.
It is known, for example from the document EP 924 227, that the use of synthetic elastomers characterized by a monomodal distribution of the molecular weights and by a polydispersity index (defined as the ratio of the weight-average molecular weight Mw to the number-average molecular weight Mn) of greater than 2 is disadvantageous to the hysteresis of the mixtures.
It is also known, from the document EP 1 278 779, that the presence of polyisoprene blocks at the chain end in the polymers described, confers, on the rubber compositions in which they are present, a reduced hysteresis and an undamaged processability.
It is also known, from the document EP 608 892, that the use of carbon black having a high specific surface makes it possible to improve the wear resistance of tires.